CVHE320 PURGE UNIT urgent

[mr hottstepper]

got a cvhe 320 and purge unit temps are like 72, 60 degrees f for the lowest wenever system tries to fully load it shuts off on hi pressure purge is not comin on (cuz temp is above 22) but what can cause this to happen sensors are reading ok i check it with another tester and the probes are ok, i even went as far as to add some refrigerant yesturday , this made it worse of course any advice?

[SFTB]

I would put a gauge on condenser and verify that pressure is actually higher than panel reads when running. Its hard to say if there's air with limited info. When you say purge isn't coming on does that mean not pumping out? All I can say is if the purge is running and suction temp is not dropping then possibly purge TXV could be bad. Subcooling could prove that. I suspect purge valves are open from what you state. Verify there is air and submit more info.

[mr hottstepper]

THE manual guage is reading the same. Purge compressor running its jus not pumping out which means there iss no air but still, the hi pressure issue is still there, this morning it was 92f, water temp was 51 dropped setpoint to 46 wen system loads pressure gradualy goes up to 16 and cut off on hi press cutout. i really dont hav much experience with the purge unit changed the purge drier yesturday incase it was saturated, at this point im totally lost

[servicetrane]

is likely to have moisture refrigeration system purge unit, the temperature should be 22 ° F suction temp unit purge air to condense

[mr hottstepper]

so ure saying that althought the suction temp is 92degf , and condensing pressure on unit is high the purge unit is workin ok?.
i now remembered something i didnt check to see if the purge is undercharged, don't have my ir meter today so i cant check sub cooling .Question if purge unit is short on refigerant for some reason will i get this , highpressure problem and will purge temp be high as well?

[Nuclrchiller]

You say that at this point you are totally lost. I agree. Your problem is high pressure, yet you have not given any info concerning saturated condenser refrigerant temperature, or entering and leaving condenser water temperatures, or entering and leaving condenser water pressures. In other words, your problem may not be with the purge unit. I can't tell from here because I don't see where you have verified the presence of air. You should have a qualified tech take a look at it.

[triggerhappy]

Shut the valves going to the purge and it should pump out in a few minutes.

Before you do that put your hand on the discharge line of the purge compressor and see what the temp. is. It should be very hot with the suction temp. that you listed for the purge.

Be very careful fooling around with the charge in the purge as it is only a few ounces.

Take sat. cond. temp. convert to pres. and compare to actual cond. pres. to tell if air is in machine.

Also check cond. water flow rate.

[SFTB]

I think the past couple replies are in the right direction and I agree with their suggestions. I don't recommend checking subcooling with an infrared because of copper's emmisivity which has to do with its reflective properties. I would use a probe. The liquid line on a purge, provided its a trane, is 1/4 " or smaller. If you have to check copper with a infrared I would spray paint it black first. May have to check discharge temp to liquid temp to trouble shoot purge because I don't think they come with a pressure access unless you add it.

[mr hottstepper]

You say that at this point you are totally lost. I agree. Your problem is high pressure, yet you have not given any info concerning saturated condenser refrigerant temperature, or entering and leaving condenser water temperatures, or entering and leaving condenser water pressures. In other words, your problem may not be with the purge unit. I can't tell from here because I don't see where you have verified the presence of air. You should have a qualified tech take a look at it.

here are the readings,
evap pressure 16hg
cond press-13.5psig
chwe-58degf diff 9degf
chwl-51degf
con-in-96degf
con-out-86degf diff 10degf
current limit setpoint is 81%
water temp set at 50degf

but my question still remains why isnt purge unit picking up non condensables and purging on its own? ill check the sub cooling thursday wen i go back there

[TheChillerMan]

here are the readings,
evap pressure 16hg
cond press-13.5psig
chwe-58degf diff 9degf
chwl-51degf
con-in-96degf
con-out-86degf diff 10degf
current limit setpoint is 81%
water temp set at 50degf

but my question still remains why isnt purge unit picking up non condensables and purging on its own? ill check the sub cooling thursday wen i go back there

because there may not be any non-condensables!

Are you sure about your entering condenser water temp and leaving condenser water temp?

96* entering water would probably cause your high condenser pressure.

You also need to check entering and leaving condenser water PRESSURE. What is the pressure differential? Too low flow will also cause high condenser pressure.

Is the chiller surging?

What are the approaches?

[servicetrane]

that coolant is 123 or 11. which is the temperature of saturated cond gives all possible information in advance by the pressure of the condenser air in the system appears

[TheChillerMan]

that coolant is 123 or 11. which is the temperature of saturated cond gives all possible information in advance by the pressure of the condenser air in the system appears

I'm guessing your first language isn't English.

[mr hottstepper]

that coolant is 123 or 11. which is the temperature of saturated cond gives all possible information in advance by the pressure of the condenser air in the system appears

yup its r123

[mr hottstepper]

I'm guessing your first language isn't English.

sorry for the spelling errors on my part i text a lot plus i'm using my mobile . and ,english is my first language lol.

[TheChillerMan]

sorry for the spelling errors on my part i text a lot plus i'm using my mobile . and ,english is my first language lol.

I was referring to servicetrane.

[TheChillerMan]

So what are your water pressures and what is the condenser approach?

[mr hottstepper]

because there may not be any non-condensables!

Are you sure about your entering condenser water temp and leaving condenser water temp?

96* entering water would probably cause your high condenser pressure.

You also need to check entering and leaving condenser water PRESSURE. What is the pressure differential? Too low flow will also cause high condenser pressure.

Is the chiller surging?

What are the approaches?

those are the correct wtr temps most of the chillers ive worked on here run with those temps, the ambient temp here is between 85 to 88degf, i cant confirm the water pressure cause guages are screwed, but if i run the back up machine it works fine with the jus about the same condensing temps,the condenser tubes were cleaned couple months ago so. we have good water pressure(assumed), alright heat exchange in tower, thats why i was suspecting the purge unit

[mr hottstepper]

I was referring to servicetrane.

lol sry

[TheChillerMan]

those are the correct wtr temps most of the chillers ive worked on here run with those temps, the ambient temp here is between 85 to 88degf, i cant confirm the water pressure cause guages are screwed, but if i run the back up machine it works fine with the jus about the same condensing temps,the condenser tubes were cleaned couple months ago so. we have good water pressure(assumed), alright heat exchange in tower, thats why i was suspecting the purge unit

I was just verifying because you said your ENTERING water was 96*.

Verify your water flow.

If that is good then check condenser approach.

Compare actual liquid temp to condenser pressure converted to temp. If there is a difference of more than 1-2 degrees then you may have air in the chiller. The wider the difference the more air you may have.

If you have air now check out the purge unit.

Troubleshooting the purge deserves a whole thread of it's own.

[mr hottstepper]

So what are your water pressures and what is the condenser approach?

i really cant tell how many gpms on d condenser cause of the defective guages, i will carry a couple when i return there,but the redundant machine when i run it works well with those condensing tem values